Better Organic Bread: Integrating Raw Material and Process Requirements for Organic Bread Production

Summary

The UK organic wheat crop, of about 15,000 hectares, is rarely able to consistently provide flour of suitable quality to meet the needs of the baking industry. As a result, more than 50% of the requirement for wheat in the organic bread market is imported.
This project seeks to address the constraints to the expansion of the market for organic bread produced from wheat grown in the UK. This will be achieved by identifying the effect of agronomic practices on the protein content and quality of organic wheat. The work will optimise the interaction of raw material characteristics with formulation and processing approaches on bread quality. This will be achieved by establishing the effects of varieties and nitrogen applications in crop husbandry practices on wheat quality. Processing factors during milling and baking, which would improve breadmaking quality and increase the utilisation of UK grown organic wheat, will also be identified.
Field trials will be undertaken at 3 sites in the UK over four seasons, they will investigate opportunities for improvement in grain quality by evaluating varieties of spring wheat. The agronomy approaches will include rhizobial inoculation of the fertility building clover crop, use of different rates of high C:N ratio compost, late N application, and optimising the compost formulation. Production protocols will be focussed on creation of stronger and higher quality protein in organic wheat based on the hypothesis that high protein strength can be used to compensate for lower protein content. Ultimately this strategy will lead to increased utilisation of UK organic wheat which has a higher market value in the breadmaking sector.
The effect of these approaches on the functional performance of wheat for breadmaking will be quantified. Breadmaking performance will be optimised by modifications to the milling extraction rate and changes to the formulation of dough mixes and dough preparation procedures. This will provide guidelines for the breadmaking procedures required to obtain doughs with appropriate rheological properties for organic bread. These studies will establish and optimise bread production recipes and mixing conditions for organic flours and result in improvements in the quality of organic bread.
11.1 Scientific objectives
Section 9 and items in annex A indicate the extent of current knowledge and where gaps currently exist. This research is aimed at complementing current scientific understanding and filling the gaps which currently prevent effective exploitation of UK grown organic wheat. The objectives are to:
1. Establish the impact of differing nitrogen application regimes and rhizobial inoculations in organic systems on wheat yield and quality, particularly protein quality and protein quantity. In particular
· Optimise nitrogen fixation and retention during the grass clover ley fertility building period by use of rhizobial seed innocula.
· Increase mineralisation driven nitrogen inputs during later stages of crop development. Compost containing high C: N ratio is thought to release a higher proportion of nitrogen through mineralisation of organic matter later in the season.
· Quantify the contribution of supplementary nitrogen inputs from manures and slurries applied later in the growing season.
2. Determine how different wheat varietal types respond to organic cultivation techniques by optimising the production protocols and identifying how these impact on key quality attributes.
· Identify wheat varieties which provide a suitable balance of protein content and quality through their ability to utilise organic nitrogen supply regimes and which provide a raw material of good quality to the breadmaking industry under UK conditions.
3. Determine the effect of reduced milling extraction rate in white flour and particle size in wholemeal flour on the protein quality and overall baking quality of (a) different wheat varietial types and (b) wheat produced with different fertility management regimes
4. Establish and optimise bread production recipes and mixing conditions for organic flours with different combinations of quality characteristics (protein content and protein content and composition.